This invention relates generally to tactile detection embedment plates used in pedestrian walkways, and more particularly to tactile detection plates aligned with a bracket and/or releasably joined together with a bracket connector.
The Department of Justice (DOJ) oversees implementation and enforcement of the Americans with Disabilities Act (ADA), and has mandated that many walkway surfaces include some form of tactile detection for visually impaired persons. One of the primary ways to provide tactile detectors near hazardous locations (e.g., roadways, railroad crossings, etc.) is with embedment plates having distinctive surface patterns of domes detectable by cane or underfoot to alert the visually impaired that they are approaching potential hazards.
Municipalities, non-governmental entities, such as land developers, railroad companies and others who likewise need to provide tactile-detectable surfaces in pedestrian walkways obviously seek low-cost solutions to implement and maintain tactile surfaces. Various embedment plates, plate materials, and methods for installing plates are known. For example, known plates are made of plastic, steel, and cast iron having tactile surfaces with truncated domes extending upward from the plates. The plates are typically rectangular, triangular wedge square or radial in shape and are installed in concrete or asphalt during construction of the walkway.
Some of these devices are made out of flimsy plastic and are subject to ultraviolet light damage, deterioration and cracking in short periods of time. Also, inherent in the truncated dome design is the exposure of domes to severe impacts by snowplow equipment, particularly snowplow blades and end-loader buckets. Domes made of plastic tend to be sheared off, nicked or cracked when snowplows hit them. Once damaged, the entire plastic embedment plate must be removed and replaced. Attempts to address these problems can be found in U.S. Pat. Nos. 5,775,835 to Szekely; 6,449,790 to Szekely; 6,715,956 to Weber et al.; and, U.S. Patent Application Publication US 2004/00428 to Provenzano, III. However, each one of these disclosures suffers from one or more disadvantages.
Steel and cast iron embedment plates are also used. Cast iron plates in particular can be extremely heavy. The size of typical cast iron detectable warning plates are two feet by two feet (2′×2′) and weigh approximately 70 lbs. (+/−) each. Typical curb opening ramp widths are a minimum of four feet (4′) wide so it normally requires two plates for typical curb ramps. Since the current plates are heavy, it normally takes two people to safely lift and place one plate at a time into a concrete ramp. Smaller and lighter weight cast iron plates that are less labor intensive, easier to handle, and install into concrete or asphalt are desirable for general safety reasons. When multiple embedment plates are used, they must be installed edge-to-edge and co-planar with one another. Even skilled and patient installers can find it difficult to properly install large heavy embedment plates in concrete and asphalt. It is particularly difficult when two (2) or more 70 lb. cast iron plates have to be set side by side in fresh concrete or asphalt. Steel and cast iron plates are desirable for durability and strength, so precise installation remains a challenge with heavy two foot (2′×2′) square cast iron plates.
Thus, there is a need for a lighter and durable embedment plate that can be easily aligned with and/or joined to the sides of adjoining plates.